Luminophore composition for low pressure discharge lamps

• US 8,941,294 B2
• Filed: 10/25/2010
• Issued: 01/27/2015
• Est. Priority Date: 11/09/2009
• Status: Active Grant

• Current Assignee: LEDVANCE GmbH (MLS Co. Ltd.)
• Original Assignee: OSRAM Licht AG (Ams-Osram AG)
• Inventors: Goebel, Nina, Held, Claudia, Konrad, Armin
• Primary Examiner(s): Mai, Anh
• Assistant Examiner(s): Lee, Brenitra M
• Application Number:
  US13/504,973
• Publication Number:
  US 20120217866A1
• Time in Patent Office: 1,555 Days
• Field of Search: 313500-512
• US Class Current: 313/503
• CPC Class Codes: C09K 11/665 with alkali or alkaline earth metals
• CPC Class Codes: C09K 11/76 also containing phosphorus and halogen, e.g. halophosphates
• CPC Class Codes: C09K 11/7734 Aluminates
• CPC Class Codes: C09K 11/774 Borates
• CPC Class Codes: C09K 11/7774 Aluminates
• CPC Class Codes: C09K 11/778 Borates
• CPC Class Codes: H01J 61/44 Devices characterised by the luminescent material

Abstract

In various embodiments, a luminophore composition for low pressure discharge lamps for generating radiation with a color temperature of greater than 4800 K having a very good general color rendering index of greater than 90, the luminophore composition including at least one halophosphate luminophore, a luminophore emitting in the red wavelength region, a luminophore emitting in the blue-green wavelength region, a europium-doped luminophore emitting in the blue wavelength region and a Tb-doped luminophore emitting in the green wavelength region, wherein the luminophore composition includes a luminophore emitting in an emission range in the visible region with wavelengths of greater than 380 nm and at least one emission band in the near ultraviolet and that the emitted intensity of the luminophore is smaller in the visible region than in the near ultraviolet region.

Claims

1. A luminophore composition for low pressure discharge lamps for generating radiation with a color temperature of greater than 4800 K having a very good general color rendering index of greater than 90, the luminophore composition comprising at least one halophosphate luminophore, a luminophore emitting in the red wavelength region, a luminophore emitting in the blue-green wavelength region, a europium-doped luminophore emitting in the blue wavelength region and a Tb-doped luminophore emitting in the green wavelength region, wherein the luminophore composition comprises a luminophore emitting in an emission range in the visible region with wavelengths of greater than 380 nm and at least one emission band in the near ultraviolet and that the emitted intensity of the luminophore is smaller in the visible region than in the near ultraviolet region.

2. The luminophore composition as claimed in claim 1, wherein the intensity emitted in the visible region by the luminophore having an emission range in the visible spectral region, which also has at least one emission band in the near ultraviolet region, is between 2% and 20% of the intensity emitted by the luminophore in the near ultraviolet.

3. The luminophore composition as claimed in claim 1, wherein europium-doped strontium tetraborate, SrB₄O₇:

Eu, and/or europium-doped strontium magnesium phosphate SrMgP₂O₇;

Eu and/or europium-doped strontium barium-aluminum silicate (Sr,Ba)Al₂Si₂O₅;

Eu and/or europium-doped strontium phosphate Sr₃(PO₄);

Eu and/or calcium tungstate CaWO₄ is provided as the luminophore emitting in the UV-A.

4. The luminophore composition as claimed in claim 1, wherein the proportion by weight of luminophore emitting in the UV-A region relative to the luminophore composition can be between 5% and 30% and, in particular, between 10% and 15%.

5. The luminophore composition as claimed in one of the claim 1, wherein Sb and Mn-doped calcium halophosphate Ca₁₀(PO₄)₆(F,Cl)₂:

Sb,Mn,Cl is provided as the halophosphate luminophore.

6. The luminophore composition as claimed in one of the claim 1, wherein the proportion by weight of halophosphate luminophore relative to the luminophore composition is between 20% and 26%.

7. The luminophore composition as claimed in claim 1, wherein Ce and Mn-doped gadolinium zinc magnesium pentaborate Gd(Zn,Mg)B₅O₁₀:

Ce,Mn is provided as the luminophore emitting in the red wavelength region.

8. The luminophore composition as claimed in claim 1, wherein the proportion by weight of luminophore emitting in the red wavelength region relative to the luminophore composition is between 30% and 36%.

9. The luminophore composition as claimed in claim 1, wherein Eu-doped strontium aluminate Sr₄Al₁₄O₂₅:

Eu is provided as the luminophore emitting in the blue-green wavelength region.

10. The luminophore composition as claimed in claim 1, wherein the proportion by weight of luminophore emitting in the blue-green wavelength region relative to the luminophore composition is between 20% and 26%.

11. The luminophore composition as claimed in claim 1, wherein the luminophore composition contains Tb-doped cerium magnesium aluminate CeMgAl₁₁O₁₉:

Tb as the Tb-doped luminophore emitting in the green wavelength region.

12. The luminophore composition as claimed in claim 1, wherein the proportion by weight of the Tb-doped luminophore emitting in the green wavelength region relative to the luminophore composition is between 2% and 8%.

13. The luminophore composition as claimed in claim 1, wherein Eu-doped barium magnesium aluminate BaMgAl₁₀O₁₇:

Eu and/or Eu and Mn-doped barium magnesium aluminate BaMg₂Al₁₆O₂₇;

Eu,Mn and/or Eu-doped strontium chlorophosphate Sr₁₀(PO₄)Cl₂;

Eu and/or Eu-doped strontium calcium chlorophosphate (Sr,Ca)₁₀(PO₄)Cl₂;

Eu is provided as the europium-doped luminophore emitting in the blue wavelength region.

14. The luminophore composition as claimed in claim 1, wherein the proportion by weight of the Eu-doped luminophore emitting in the blue wavelength region relative to the luminophore composition is between 0% and 6%.

15. The luminophore composition as claimed in claim 1, wherein a luminophore emitting in the dark red wavelength region, in particular Mn-doped magnesium fluorogermanate Mg₄FGeO₅₅:

Mn is provided.

16. The luminophore composition as claimed in claim 15, wherein the proportion by weight of luminophore emitting in the dark red wavelength region relative to the luminophore composition is between 0% and 5%.

17. A low pressure discharge lamp comprising a discharge vessel and a luminophore composition applied to the inside thereof, wherein the luminophore coating comprises a luminophore composition as claimed in claim 1.